(It doesn’t pay its own taxes.

I don't know your living situation but if your paying x,xxx for rent or a mortgage and instead by living in one side and renting out the other you will be paying y,yyy instead and y is less then x that's great, especially if you can rent out your primary residence and make income there too. 

We had an accounting system once that necessitated doing this - not ideal, but it keeps the assets and liabilities straight and AP is just an accrual until you pay the bill.

Look for safe accounts that pay good interest or dividends to grow your security.

Throughout this entire time, I waited tables and bartended at night to pay rent.

Pay attention to how professional and transparent they are.Avoid Pressure Tactics: Scammers often pressure you to act quickly.

You will pay them and everything will then fall apart.

Also, how does one assess whether or not one can turn a profit after paying principal/interest, insurance, and taxes each month?

You will also likely be paying more than more experienced investors as you build your team and knowledge.

However, one idea to consider is some "middle ground" for your investing...